At the opening of the trial at Reading Crown Court on Wednesday, May 2, jurors heard how he later fled the scene, leaving it to his wife’s cousin to make the horrifying discovery.

Forensic evidence showed Mrs Grainger, a 30-year-old mother of two who worked for Triangle Pharmacy in Tilehurst, had been strangled and battered about the head with a blunt object.

Traces of her blood were found on the base of a heavy saucepan.

Francis Fitzgibbon QC, prosecuting, said neighbours reported hearing a series of thumps in the early hours of November 4 last year and the crown’s case is that they were made by Mr Grainger as he murdered his wife.

The court heard the couple had a tempestuous relationship and regularly quarreled over 32-year-old Mr Grainger’s cocaine and alcohol binges during which he would disappear for days at a time.

In one angry text read to the jury, she branded him a “raging cokehead”.

In another she pleaded: “I want a normal life. I don’t want a druggie husband.

“You’re gradually breaking everything. Why are you so strange? I can’t trust you.

“Normal is cutting the grass without being asked; normal is not taking ‘coke’ for days.”

Mr Fitzgibbon said: “The crown say these are messages from a wife and mother who felt badly let down by her feckless husband.”

He also told jurors that Mr Grainger once confessed to a work colleague about an occasion on which he put his hands round his wife’s throat and began to strangle her.

Mr Fitzgibbon added: “Knowing what you do about how she died from strangulation, you may think this is an important confession from the defendant.”

Matters came to a head when Mr Grainger went missing when he was due to take his wife and children on a family holiday, the jury heard.

The relationship continued to deteriorate, prompting Mr Grainger to move out and to move in with his mother, said Mr Fitzgibbon.

However, on the eve of her murder, Mrs Grainger had enjoyed a “girls’ night in” at her home but also invited her husband to stay over.

When her girlfriends went home, Mrs Grainger went upstairs to bed but her husband stayed downstairs.

The jury has been told that he often used to creep downstairs as she slept to indulge in solitary cocaine binges.

On the fateful night, said Mr Fitzgibbon, she sent him a text message in the early hours which said: “What are you doing, weirdo? I don’t trust you.”

He texted back: “I’m not doing nothing. I’ve just got a tight chest and I’m restless.”

Mr Fitzgibbons asked: “Did those texts indicate the re-opening of an old quarrel that escalated and turned violent?”

It was around that time, the court heard, that neighbours heard a series of loud thumps.

Mr Fitzgibbons said: “It’s likely that what they heard was the defendant battering Simone’s head against something.

“Following the killing it seems the defendant spent some time trying to clean up traces of blood.”

Jurors heard that Mr Grainger then made a series of phone calls, including one to his dealer asking for cocaine to be delivered and left under the front door mat.

“Sandra is a prostitute – someone who provides escort services, to use a euphemism.

“And he was communicating with other providers of escort services at this time.

“He made no attempt to get help.

“There was no call to the emergency services.

“It may be the defendant’s case that he killed his wife unintentionally or in self defence or under such extreme stress that he lost his self control and so what he did wasn’t an act of murder.

“If any of those things happened, you may think that by now – the morning after she died – he must be wracked by remorse.

“But instead of calling the emergency services, why is he contacting prostitutes... and asking for drugs?”

Around 8am that day, Mr Grainger left the house and bought cigarettes and a fizzy drink at a nearby store, then drove to his mother’s house, the court heard.

By now, Mrs Grainger’s friends and family were concerned for her welfare as she had not turned up for a hair appointment and was not answering her phone.

At 11am, her cousin used her own key to enter the Mrs Grainger’s home.

Mr Fitzgibbon said: “As you can imagine, she was horrified to discover her body lying face down in the back of the kitchen.

“She ran into the street, screaming.”

The emergency services were called and paramedics attempted resuscitation but it was clear it was too late to save Mrs Grainger, jurors heard.

Meanwhile, Mr Grainger had left his mother’s home, but around 6.30pm the following day he was arrested as he turned up again on her doorstep.

He told officers: “I know why you’re here,” the court heard.

Later he made no comment to police questions but, accompanied by his legal representative, gave a prepared statement.

It said: “I was at home with my wife... I wasn’t drunk and I hadn’t taken any illegal drugs.”

He said he and his wife had sex and that he had stayed downstairs.

The statement added: “Between 1am and 3am she came downstairs and started shouting at me: ‘I just want a normal husband.’

“She tried to hit me multiple times with a clenched fist.”

Mr Grainger said in the ensuing struggle she fell and hit her head but then went and got a pair of scissors and attacked him with them.

The statement went on: “She said: ‘I wish you were dead, why don’t you kill yourself?’

“I grabbed her neck; I wasn’t trying to hurt her, I was trying to restrain her.”

Mr Grainger said she was still trying to attack him with the scissors when “after 30 seconds she felt heavy. I let her go and she fell forward onto the floor. She was lying on the floor muttering and swearing at me.”

The statement said that he then went to bed and, when he came down at 5.30am, her found her still lying there, dead.

He concluded by saying he rolled the body in a blanket and that he was “acting at all times in self defence”.

Post mortem tests showed Mrs Grainger died from compression of the neck and blunt force trauma to the head.

In addition, her nose and right cheek had been broken, her nails were torn and her larynx was fractured.

Injuries to her mouth suggested something soft had been pressed against it and there were more traces of her blood found on a cushion and the base of a saucepan, the court heard.

Toxicology tests showed Mr Grainger was a “heavy and regular user” of cocaine and there was Viagra in his system.

Mr Grainger denies both murder and manslaughter and the trial, expected to last around three weeks, continues.